Validation error for ResponseTextDeltaEvent after updating to 1.97.1

[rudra-attri]

Confirm this is an issue with the Python library and not an underlying OpenAI API

• This is an issue with the Python library

Describe the bug

using litellm models in openai-agents with openai version 1.97.1 causes this error in streaming mode. Note that this was working fine with openai 1.96.1

pydantic_core._pydantic_core.ValidationError: 1 validation error for ResponseTextDeltaEvent
logprobs
Field required [type=missing, input_value={'content_index': 0, 'del...', 'sequence_number': 3}, input_type=dict]
For further information visit https://errors.pydantic.dev/2.11/v/missing

To Reproduce

import asyncio
from agents import Agent, Runner
from dotenv import load_dotenv
from openai.types.responses import ResponseTextDeltaEvent

load_dotenv()

async def main():
print("\n🚀 Running basic mode...")
agent = Agent(
name="Test Agent",
instructions="You are a helpful assistant that can help with tasks.",
model="litellm/anthropic/claude-opus-4-20250514"
)
result = Runner.run_streamed(
starting_agent=agent,
input="Hi",
)

print("=== Test Agent Starting ===")
async for event in result.stream_events():
        if event.type == "raw_response_event" and isinstance(event.data, ResponseTextDeltaEvent):
            print(event.data.delta, end="", flush=True)
    
    
print(result.to_input_list())

if name == "main":
asyncio.run(main())

Code snippets

OS

macOS

Python version

Python v3.11.6

Library version

openai 1.97.1, openai-agents 0.2.3, litellm 1.74.7

[kaka1nices]

The reason for the bug is that the openai agents SDK added logprobes in ResponseTextDeltaEvent to adapt to openai version 1.97.1, but did not take into account that many users call other agent models and cannot output logprobes.
https://github.com/openai/openai-python/blob/main/src/openai/types/responses/response_text_delta_event.py

class ResponseTextDeltaEvent(BaseModel):
    content_index: int
    """The index of the content part that the text delta was added to."""

    delta: str
    """The text delta that was added."""

    item_id: str
    """The ID of the output item that the text delta was added to."""

    logprobs: List[Logprob]
    """The log probabilities of the tokens in the delta."""

    output_index: int
    """The index of the output item that the text delta was added to."""

    sequence_number: int
    """The sequence number for this event."""

    type: Literal["response.output_text.delta"]
    """The type of the event. Always `response.output_text.delta`."""

link:openai/openai-agents-python#715

[Ai80-8]

Stop